“@TSB payday and I can’t even access my online banking AGAIN,” one added.

TSB did not confirm how many people were affected by the latest glitch but we spotted hundreds of tweets.

A spokesperson for TSB first told The Sun Online: “We’re aware that our mobile app is currently unavailable for some customers – we’re really sorry for the inconvenience this may cause.

“Our internet banking site, accessed via www.tsb.co.uk, is working as normal and we recommend our customers access their accounts there. We are working as hard and as fast as possible to get the mobile app back up and working fully.”

TSB meltdown: what are your rights?

IF you’re one of the potentially millions of customers affected by TSB’s online banking problems then here are your rights.

Will your expenses be covered? If you suffer knock-on costs then the bank has confirmed it will reimburse you. Make a note of dates, keep receipts and a log of how much you’ve been left out of pocket.

What are the alternatives? Visit a branch or try telephone banking if you urgently need to access cash.

Is it a data breach? The bank has denied that there has been a data breach but we’ve asked for more information on this and will update asap. Don’t spend money in your account that isn’t yours as you will be liable to pay it back.

How to complain about your bank? Firstly, complain to TSB. If the problem is not resolved to your satisfaction after 8 weeks then you can complain to the Financial Ombudsman Service

Later in the afternoon, TSB reported its online mobile app was working again – although some customers claimed they were still experiencing difficulties on Twitter.

Scammers have also been targeting TSB customers amid the chaos caused by a planned IT upgrade in April which left 1.9million customers unable to access their online banking.

The Sun Online has been inundated with calls from scores of TSB customers who have been a victim of this type of fraud over the past few weeks.

There have been 321 TSB phishing scams reported to Action Fraud since the beginning of May – up from just 30 on the month before.

We spoke with John Machin, a gym owner from Cheshire who has had his TSB bank account completely cleared out by scammers after they stole £17,000.

On Thursday, TSB apologised for yet another blunder after it emerged former customers found their direct debits had been cancelled and firms were apparently told they had died.

Have you lost money in the TSB banking meltdown? Here’s our guide on how to get it back.

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